Operating Pressures in freeze? Harvest?

An 1800 air should take longer than 6 minutes to make ice. In fact, isn't the board locked out of going in to harvest for the first 6 minutes of freeze anyway?

Bridge should be 1/8" thick.

Why salt in the water?

The ice thickness probe no longer relies on making a ground contact with the ice for it to go in to harvest. Instead, it senses the MHz frequency of the ice when it reaches the correct bridge thickness.

What has tech support told you?

 

Hi

we use to a salt to water because our water in Vancouver is very pure. and the old probes on manitowoc
would not conduct though the ice to initiate harvest. This is for the first start up.

tech support told me to change ice thickness probe, water distribution tube and the water pump. I am not sure why

when I change the board and probe the machine will go into harvest but the ice wont drop because its to small. Therefore I increase the thickness adjustment and it goes back into not harvesting and the probe gets buried in the ice. Then I manually force harvest and it drops like a rock.

The machine has been working on and off for six months.

 

Ice sensor set too close to the evaporator plate maybe

 

It makes and drops ice
No need to hook up gauges

 

Forgot the easy one
Did the black clip and washer get removed from the ice thickness sensor?

 

The other favorite oops is when the installer tosses the air baffle out instead of putting it on the back of the machine.lol

 

Clean water will affect the water level probes.

If you are adjusting the ice thickness sensor while it is running in the freeze cycle you are messing with the sound limits that it is setting in the first 6 minutes that are locked in.

 

You need to do and Ice Probe sound test, go into the following menus: service/real time date/time and temp, scroll all the way down untill you see the 100hz and 120hz. there will be numbers next to them. See if the numbers go up when you scratch the probe 'bump' If they do the probe is ok.

What is the software version? go Menu/machine info/ Main SW ver.

If the probe does react properly and after the 6 min lock in is over and it still will not switch into a harvest mode you might be looking at a new board.

The water pump thing can cause random freeze ups

Diagnostics

1. Turn off power and inspect ice thickness probe for
physical damage. Look for bulging, cracks around
the nipple or deformed pivot pins.
2. Verify ice thickness probe gap is approximately
9/32” (7 mm)
3. Make sure the ice thickness probe wire doesn’t
restrict movement.
4. Perform Ice Thickness Probe tap test:
• Press the menu button, scroll down to Service,
press the right arrow, scroll down to Real Time
Data, press right arrow - With the brackets around
Time & Temp press the right arrow - Scroll down
until 100Hz &120Hz are displayed. Slowly
increasing and decreasing numbers typically in the
200Hz to 300Hz range will display to the right of
100Hz &120Hz.
• Lift the Ice Thickness Probe and continuously tap
the nipple while watching the numbers to the right
of the 100Hz and 120Hz. There is a slight delay
while tapping.
Pass Numbers increasing into the thousands indicates a
properly working ice thickness probe and control
board.
Fail Numbers do not move or do not increase into the
thousands - Ohm the ice thickness probe.180 Part Number STH025 7/13
5. Ohm Ice Thickness Probe
NOTE: Verify meter leads are properly connected to
VOM with the red meter lead connected to positive &
the black meter lead connected to negative
• Disconnect Ice Thickness Probe from control
board
• Connect red meter lead to the red wire and the
black meter lead to the black wire - Normal
readings = 1.4 to 2.5 KΩ's.
• Reverse leads - Connect black meter lead to the
red wire, red meter lead to the black wire - Normal
readings = 1.2 to 1.5 KΩ's.
6. Check control board voltage
• Set VOM to DC voltage scale - Check voltage
across the top and bottom pin - Normal readings =
3.25 to 3.35 VDC.
Pass Ohm values are within range - Check control board
voltage at the ice thickness probe connection.
Fail Replace ice thickness probe.
Pass Control board voltage is normal
Fail Replace control board

 

What did you set the Ice Thickness Probe? Should be 9/32"

http://www.manitowocice.com/asset/?id=pnvoq

See Page 100 for setting Probe.

"During the first 6 minutes of the freeze cycle the ice
thickness probe microphone samples ambient noise. 6
minutes into the freeze cycle 4 baseline readings are
recorded. Ice formation on the evaporator will change
the readings; when two of the four baseline readings
are exceeded a harvest cycle starts."

 

Another thing too, do you have good water flow across the evaporator. If you're not getting good water flow, you could have an area behind the ice thickness probe where there is no ice. I've seen that happen a couple times.

 

The machine makes great ice in about 6 minutes

Start here. This isn't normal.

 

Make sure the water pump is pushed firmly up into its mount.

Sent from my ADR6350 using Tapatalk 2